The World Trade Organisation (WTO) has upheld a complaint that China discriminates against American suppliers of electronic payment services.

China requires all domestic credit and debit cards to carry the logo of the state-owned China Union Pay, and for all payment terminals to accept the company's cards.

The WTO has found that China is violating trade rules by enforcing regulations that create a monopoly for China Union Pay in a market worth more than $US1 trillion annually.

The United States filed the complaint with the WTO and has welcomed the ruling.

US trade representative Ron Kirk says the decision will allow US companies to compete on a level playing field in China.

"This decision will help US companies and increase American jobs as a more efficient credit and debit payment system in China enables consumers to buy more goods, including quality, made-in-America products," he said.

He says the US stands to gain 6,000 jobs relating to electronic payment services as a result of the decision.

The White House has turned the decision into a presidential issue, with Spokesman Jay Carney saying it's evidence President Barack Obama is willing to tackle China's "unfair" trade practices.

Meanwhile, Republican rival Mitt Romney has pledged to get tough with China over its massive trade surplus.

He says he would declare China a currency manipulator, paving the way for sanctions, on his first day in office.